ps: Apply the clip reduction techniques from pdf

If the clip wholly covers the operation, we do not need to set one, and
if the current clip similarly covers the operation we do not to unset
it.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 32 insertions, 4 deletions

diff --git a/src/cairo-ps-surface.c b/src/cairo-ps-surface.c
index 4b8ce801..4d1c3214 100644
--- a/src/cairo-ps-surface.c
+++ b/src/cairo-ps-surface.c
@@ -3557,6 +3557,34 @@ _cairo_ps_surface_get_font_options (void                  *abstract_surface,
 }
 
 static cairo_int_status_t
+_cairo_ps_surface_set_clip (cairo_ps_surface_t *surface,
+			    cairo_composite_rectangles_t *composite)
+{
+    cairo_clip_t *clip = composite->clip;
+
+    if (_cairo_clip_is_region (clip) &&
+	cairo_region_contains_rectangle (_cairo_clip_get_region (clip),
+					 &composite->unbounded) == CAIRO_REGION_OVERLAP_IN)
+    {
+	    clip = NULL;
+    }
+
+    if (clip == NULL) {
+	cairo_clip_t *current = surface->clipper.clip;
+
+	if (current && _cairo_clip_is_region (current) &&
+	    cairo_region_contains_rectangle (_cairo_clip_get_region (current),
+					     &composite->unbounded) == CAIRO_REGION_OVERLAP_IN)
+	{
+	    return CAIRO_STATUS_SUCCESS;
+	}
+    }
+
+    return _cairo_surface_clipper_set_clip (&surface->clipper, clip);
+}
+
+
+static cairo_int_status_t
 _cairo_ps_surface_paint (void			*abstract_surface,
 			 cairo_operator_t	 op,
 			 const cairo_pattern_t	*source,
@@ -3584,7 +3612,7 @@ _cairo_ps_surface_paint (void			*abstract_surface,
 				 "%% _cairo_ps_surface_paint\n");
 #endif
 
-    status = _cairo_surface_clipper_set_clip (&surface->clipper, clip);
+    status = _cairo_ps_surface_set_clip (surface, &extents);
     if (unlikely (status))
 	return status;
 
@@ -3665,7 +3693,7 @@ _cairo_ps_surface_stroke (void			*abstract_surface,
 				 "%% _cairo_ps_surface_stroke\n");
 #endif
 
-    status = _cairo_surface_clipper_set_clip (&surface->clipper, clip);
+    status = _cairo_ps_surface_set_clip (surface, &extents);
     if (unlikely (status))
 	return status;
 
@@ -3727,7 +3755,7 @@ _cairo_ps_surface_fill (void		*abstract_surface,
     if (unlikely (status))
 	return status;
 
-    status = _cairo_surface_clipper_set_clip (&surface->clipper, clip);
+    status = _cairo_ps_surface_set_clip (surface, &extents);
     if (unlikely (status))
 	return status;
 
@@ -3804,7 +3832,7 @@ _cairo_ps_surface_show_glyphs (void		     *abstract_surface,
 				 "%% _cairo_ps_surface_show_glyphs\n");
 #endif
 
-    status = _cairo_surface_clipper_set_clip (&surface->clipper, clip);
+    status = _cairo_ps_surface_set_clip (surface, &extents);
     if (unlikely (status))
 	return status;